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qcode.go
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qcode.go
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//go:generate stringer -type=QType,MType,SelType,SkipType,PagingType,AggregrateOp,ValType -output=./gen_string.go
package qcode
import (
"encoding/json"
"errors"
"fmt"
"strconv"
"strings"
"sync"
"github.com/dosco/graphjin/core/internal/graph"
"github.com/dosco/graphjin/core/internal/sdata"
"github.com/dosco/graphjin/core/internal/util"
)
const (
maxSelectors = 30
)
type QType int8
const (
QTUnknown QType = iota
QTQuery
QTSubscription
QTMutation
QTInsert
QTUpdate
QTDelete
QTUpsert
)
type SelType int8
const (
SelTypeNone SelType = iota
SelTypeUnion
SelTypeMember
)
type SkipType int8
const (
SkipTypeNone SkipType = iota
SkipTypeUserNeeded
SkipTypeRemote
)
type QCode struct {
Type QType
SType QType
ActionVar string
Selects []Select
Vars Variables
Roots []int32
rootsA [5]int32
Mutates []Mutate
MCounts map[string]int32
Schema *sdata.DBSchema
}
type Select struct {
ID int32
ParentID int32
UParentID int32
Type SelType
Singular bool
Typename bool
Table string
FieldName string
Cols []Column
ColMap map[string]int
ArgMap map[string]Arg
Funcs []Function
Where Filter
OrderBy []OrderBy
GroupCols bool
DistinctOn []sdata.DBColumn
Paging Paging
Children []int32
SkipRender SkipType
Ti sdata.DBTableInfo
Rel sdata.DBRel
order Order
through string
}
type Column struct {
Col sdata.DBColumn
FieldName string
Base bool
}
type Function struct {
Name string
Col sdata.DBColumn
FieldName string
skip bool
}
type Filter struct {
*Exp
}
type Exp struct {
Op ExpOp
Table string
Rels []sdata.DBRel
Col sdata.DBColumn
Type ValType
Val string
ListType ValType
ListVal []string
Children []*Exp
childrenA [5]*Exp
internal bool
doFree bool
}
type Arg struct {
Val string
}
var zeroExp = Exp{doFree: true}
func (ex *Exp) Reset() {
*ex = zeroExp
}
func (ex *Exp) Free() {
if !ex.doFree {
expPool.Put(ex)
}
}
type OrderBy struct {
Col sdata.DBColumn
Order Order
}
type PagingType int8
const (
PTOffset PagingType = iota
PTForward
PTBackward
)
type Paging struct {
Type PagingType
LimitVar string
Limit int32
OffsetVar string
Offset int32
Cursor bool
NoLimit bool
}
type ExpOp int8
const (
OpNop ExpOp = iota
OpAnd
OpOr
OpNot
OpEquals
OpNotEquals
OpGreaterOrEquals
OpLesserOrEquals
OpGreaterThan
OpLesserThan
OpIn
OpNotIn
OpLike
OpNotLike
OpILike
OpNotILike
OpSimilar
OpNotSimilar
OpRegex
OpNotRegex
OpIRegex
OpNotIRegex
OpContains
OpContainedIn
OpHasKey
OpHasKeyAny
OpHasKeyAll
OpIsNull
OpTsQuery
OpFalse
OpNotDistinct
OpDistinct
OpEqualsTrue
OpNotEqualsTrue
)
type ValType int8
const (
ValStr ValType = iota + 1
ValNum
ValBool
ValList
ValVar
ValNone
ValRef
)
type AggregrateOp int8
const (
AgCount AggregrateOp = iota + 1
AgSum
AgAvg
AgMax
AgMin
)
type Order int8
const (
OrderAsc Order = iota + 1
OrderDesc
OrderAscNullsFirst
OrderAscNullsLast
OrderDescNullsFirst
OrderDescNullsLast
)
type Compiler struct {
c Config
s *sdata.DBSchema
tr map[string]trval
}
var expPool = sync.Pool{
New: func() interface{} { return &Exp{doFree: true} },
}
func NewCompiler(s *sdata.DBSchema, c Config) (*Compiler, error) {
seedExp := [100]Exp{}
for i := range seedExp {
seedExp[i].doFree = true
expPool.Put(&seedExp[i])
}
c.defTrv.query.block = c.DefaultBlock
c.defTrv.insert.block = c.DefaultBlock
c.defTrv.update.block = c.DefaultBlock
c.defTrv.upsert.block = c.DefaultBlock
c.defTrv.delete.block = c.DefaultBlock
return &Compiler{c: c, s: s, tr: make(map[string]trval)}, nil
}
func NewFilter() *Exp {
ex := expPool.Get().(*Exp)
ex.Reset()
ex.internal = true
return ex
}
type Variables map[string]json.RawMessage
func (co *Compiler) Compile(query []byte, vars Variables, role string) (*QCode, error) {
var err error
qc := QCode{SType: QTQuery, Schema: co.s, Vars: vars}
qc.Roots = qc.rootsA[:0]
op, err := graph.Parse(query, co.c.FragmentFetcher)
if err != nil {
return nil, err
}
switch op.Type {
case graph.OpQuery:
qc.Type = QTQuery
case graph.OpSub:
qc.Type = QTSubscription
case graph.OpMutate:
qc.Type = QTMutation
default:
return nil, fmt.Errorf("invalid operation: %s", op.Type)
}
if err := co.compileQuery(&qc, &op, role); err != nil {
return nil, err
}
if qc.Type == QTMutation {
if err = co.compileMutation(&qc, &op, role); err != nil {
return nil, err
}
}
return &qc, nil
}
func (co *Compiler) compileQuery(qc *QCode, op *graph.Operation, role string) error {
var id int32
if len(op.Fields) == 0 {
return errors.New("invalid graphql no query found")
}
if op.Type == graph.OpMutate {
if err := co.setMutationType(qc, op.Fields[0].Args); err != nil {
return err
}
}
qc.Selects = make([]Select, 0, 5)
st := util.NewStackInt32()
if len(op.Fields) == 0 {
return errors.New("empty query")
}
for _, f := range op.Fields {
if f.ParentID == -1 {
val := f.ID | (-1 << 16)
st.Push(val)
}
}
for {
if st.Len() == 0 {
break
}
if id >= maxSelectors {
return fmt.Errorf("selector limit reached (%d)", maxSelectors)
}
val := st.Pop()
fid := val & 0xFFFF
parentID := (val >> 16) & 0xFFFF
field := &op.Fields[fid]
// A keyword is a cursor field at the top-level
// For example posts_cursor in the root
if field.Type == graph.FieldKeyword {
continue
}
if field.ParentID == -1 {
parentID = -1
}
s1 := Select{
ID: id,
ParentID: parentID,
ColMap: make(map[string]int, len(field.Children)),
}
sel := &s1
if field.Alias != "" {
sel.FieldName = field.Alias
} else {
sel.FieldName = field.Name
}
sel.Children = make([]int32, 0, 5)
if err := co.compileDirectives(qc, sel, field.Directives); err != nil {
return err
}
if err := co.addRelInfo(field, qc, sel); err != nil {
return err
}
var tr trval
if sel.Ti.IsAlias {
tr = co.getRole(role, sel.Ti.Name)
} else {
tr = co.getRole(role, field.Name)
}
if tr.isSkipped(qc.Type) {
sel.SkipRender = SkipTypeUserNeeded
} else {
if err := tr.isBlocked(qc.SType, field.Name); err != nil {
return err
}
}
if err := co.compileArgs(qc, sel, field.Args, role); err != nil {
return err
}
if err := co.compileColumns(field, op, st, qc, sel, tr); err != nil {
return err
}
// Order is important AddFilters must come after compileArgs
if un := addFilters(qc, sel, tr); un && role == "anon" {
sel.SkipRender = SkipTypeUserNeeded
}
// If an actual cursor is avalable
if sel.Paging.Cursor {
// Set tie-breaker order column for the cursor direction
// this column needs to be the last in the order series.
if err := co.orderByIDCol(sel); err != nil {
return err
}
// Set filter chain needed to make the cursor work
if sel.Paging.Type != PTOffset {
co.addSeekPredicate(sel)
}
}
co.setLimit(tr, qc, sel)
if err := co.validateSelect(sel); err != nil {
return err
}
qc.Selects = append(qc.Selects, s1)
id++
}
if id == 0 {
return errors.New("invalid query")
}
return nil
}
func (co *Compiler) addRelInfo(field *graph.Field, qc *QCode, sel *Select) error {
var psel *Select
var pname string
var sinset bool
var err error
if sel.ParentID == -1 {
qc.Roots = append(qc.Roots, sel.ID)
} else {
psel = &qc.Selects[sel.ParentID]
psel.Children = append(psel.Children, sel.ID)
pname = psel.Table
}
if sel.Ti, err = co.s.GetTableInfoB(field.Name, pname); err != nil {
return err
}
sel.Table = sel.Ti.Name
switch field.Type {
case graph.FieldUnion:
sel.Type = SelTypeUnion
if psel == nil {
return fmt.Errorf("union types are only valid with polymorphic relationships")
}
sel.Rel, err = co.s.GetRel(field.Name, psel.Table, sel.through)
case graph.FieldMember:
// TODO: Fix this
// if sel.Table != sel.Table {
// return fmt.Errorf("inline fragment: 'on %s' should be 'on %s'", sel.Table, sel.Table)
// }
sel.Type = SelTypeMember
sel.Singular = psel.Singular
sel.UParentID = psel.ParentID
sinset = true
ppsel := qc.Selects[sel.UParentID]
sel.Rel, err = co.s.GetRel(psel.Table, ppsel.Table, "")
default:
switch sel.Rel.Type {
case sdata.RelSkip:
sel.Rel.Type = sdata.RelNone
default:
if psel != nil {
sel.Rel, err = co.s.GetRel(sel.Table, psel.Table, sel.through)
}
}
}
if err != nil {
return err
}
if !sinset {
sel.Singular = (sel.Ti.IsSingular)
}
return nil
}
func (co *Compiler) setLimit(tr trval, qc *QCode, sel *Select) {
// Use limit from table role config
if l := tr.limit(qc.Type); l != 0 {
sel.Paging.Limit = l
// Else use default limit from config
} else if co.c.DefaultLimit != 0 {
sel.Paging.Limit = int32(co.c.DefaultLimit)
// Else just go with 20
} else {
sel.Paging.Limit = 20
}
}
// This
// (A, B, C) >= (X, Y, Z)
//
// Becomes
// (A > X)
// OR ((A = X) AND (B > Y))
// OR ((A = X) AND (B = Y) AND (C > Z))
// OR ((A = X) AND (B = Y) AND (C = Z)
func (co *Compiler) addSeekPredicate(sel *Select) {
var or, and *Exp
obLen := len(sel.OrderBy)
if obLen != 0 {
isnull := NewFilter()
isnull.Op = OpIsNull
isnull.Type = ValRef
isnull.Table = "__cur"
isnull.Col = sel.OrderBy[0].Col
isnull.Val = "true"
or = NewFilter()
or.Op = OpOr
or.Children = append(or.Children, isnull)
}
for i := 0; i < obLen; i++ {
if i != 0 {
and = NewFilter()
and.Op = OpAnd
}
for n, ob := range sel.OrderBy {
if n > i {
break
}
f := NewFilter()
f.Type = ValRef
f.Table = "__cur"
f.Col = ob.Col
f.Val = ob.Col.Name
switch {
case i > 0 && n != i:
f.Op = OpEquals
case ob.Order == OrderDesc:
f.Op = OpLesserThan
default:
f.Op = OpGreaterThan
}
if and != nil {
and.Children = append(and.Children, f)
} else {
or.Children = append(or.Children, f)
}
}
if and != nil {
or.Children = append(or.Children, and)
}
}
setFilter(sel, or)
}
func addFilters(qc *QCode, sel *Select, tr trval) bool {
if fil, userNeeded := tr.filter(qc.SType); fil != nil {
switch fil.Op {
case OpNop:
case OpFalse:
sel.Where.Exp = fil
default:
setFilter(sel, fil)
}
return userNeeded
}
return false
}
func (co *Compiler) compileDirectives(qc *QCode, sel *Select, dirs []graph.Directive) error {
var err error
for i := range dirs {
d := &dirs[i]
switch d.Name {
case "skip":
err = co.compileDirectiveSkip(sel, d)
case "include":
err = co.compileDirectiveInclude(sel, d)
case "not_related":
err = co.compileDirectiveNotRelated(sel, d)
case "through":
err = co.compileDirectiveThrough(sel, d)
}
if err != nil {
return err
}
}
return nil
}
func (co *Compiler) compileArgs(qc *QCode, sel *Select, args []graph.Arg, role string) error {
var err error
for i := range args {
arg := &args[i]
switch arg.Name {
case "id":
err = co.compileArgID(sel, arg)
case "search":
err = co.compileArgSearch(sel, arg)
case "where":
err = co.compileArgWhere(sel.Ti, sel, arg, role)
case "orderby", "order_by", "order":
err = co.compileArgOrderBy(sel, arg)
case "distinct_on", "distinct":
err = co.compileArgDistinctOn(sel, arg)
case "limit":
err = co.compileArgLimit(sel, arg)
case "offset":
err = co.compileArgOffset(sel, arg)
case "first":
err = co.compileArgFirstLast(sel, arg, OrderAsc)
case "last":
err = co.compileArgFirstLast(sel, arg, OrderDesc)
case "after":
err = co.compileArgAfterBefore(sel, arg, PTForward)
case "before":
err = co.compileArgAfterBefore(sel, arg, PTBackward)
case "find":
err = co.compileArgFind(sel, arg)
}
if err != nil {
return err
}
}
return nil
}
func (co *Compiler) validateSelect(sel *Select) error {
if sel.Rel.Type == sdata.RelRecursive {
v, ok := sel.ArgMap["find"]
if !ok {
return fmt.Errorf("arguments: 'find' needed for recursive queries")
}
if v.Val != "parents" && v.Val != "children" {
return fmt.Errorf("find: valid values are 'parents' and 'children'")
}
}
return nil
}
func (co *Compiler) setMutationType(qc *QCode, args []graph.Arg) error {
setActionVar := func(arg *graph.Arg) error {
if arg.Val.Type != graph.NodeVar {
return argErr(arg.Name, "variable")
}
qc.ActionVar = arg.Val.Val
return nil
}
for i := range args {
arg := &args[i]
switch arg.Name {
case "insert":
qc.SType = QTInsert
return setActionVar(arg)
case "update":
qc.SType = QTUpdate
return setActionVar(arg)
case "upsert":
qc.SType = QTUpsert
return setActionVar(arg)
case "delete":
qc.SType = QTDelete
if arg.Val.Type != graph.NodeBool {
return argErr(arg.Name, "boolen")
}
if arg.Val.Val == "false" {
qc.Type = QTQuery
}
return nil
}
}
return nil
}
func (co *Compiler) compileDirectiveSkip(sel *Select, d *graph.Directive) error {
if len(d.Args) == 0 || d.Args[0].Name != "if" {
return fmt.Errorf("@skip: required argument 'if' missing")
}
arg := d.Args[0]
if arg.Val.Type != graph.NodeVar {
return argErr("if", "variable")
}
ex := expPool.Get().(*Exp)
ex.Reset()
ex.Op = OpNotEqualsTrue
ex.Type = ValVar
ex.Val = arg.Val.Val
setFilter(sel, ex)
return nil
}
func (co *Compiler) compileDirectiveInclude(sel *Select, d *graph.Directive) error {
if len(d.Args) == 0 || d.Args[0].Name != "if" {
return fmt.Errorf("@include: required argument 'if' missing")
}
arg := d.Args[0]
if arg.Val.Type != graph.NodeVar {
return argErr("if", "variable")
}
ex := expPool.Get().(*Exp)
ex.Reset()
ex.Op = OpEqualsTrue
ex.Type = ValVar
ex.Val = arg.Val.Val
setFilter(sel, ex)
return nil
}
func (co *Compiler) compileDirectiveNotRelated(sel *Select, d *graph.Directive) error {
sel.Rel.Type = sdata.RelSkip
return nil
}
func (co *Compiler) compileDirectiveThrough(sel *Select, d *graph.Directive) error {
if len(d.Args) == 0 || d.Args[0].Name != "table" {
return fmt.Errorf("@through: required argument 'table' missing")
}
arg := d.Args[0]
if arg.Val.Type != graph.NodeStr {
return argErr("table", "string")
}
sel.through = arg.Val.Val
return nil
}
func (co *Compiler) compileArgFind(sel *Select, arg *graph.Arg) error {
// Only allow on recursive relationship selectors
if sel.Rel.Type != sdata.RelRecursive {
return fmt.Errorf("find: selector '%s' is not recursive", sel.FieldName)
}
if arg.Val.Val != "parents" && arg.Val.Val != "children" {
return fmt.Errorf("find: valid values 'parents' or 'children'")
}
sel.addArg(arg)
return nil
}
func (co *Compiler) compileArgID(sel *Select, arg *graph.Arg) error {
if sel.ParentID != -1 {
return fmt.Errorf("argument 'id' can only be specified at the query root")
}
if sel.Ti.PrimaryCol.Name == "" {
return fmt.Errorf("no primary key column defined for %s", sel.Table)
}
if arg.Val.Type != graph.NodeVar {
return argErr("id", "variable")
}
ex := expPool.Get().(*Exp)
ex.Reset()
ex.Op = OpEquals
ex.Type = ValVar
ex.Val = arg.Val.Val
ex.Col = sel.Ti.PrimaryCol
sel.Where.Exp = ex
return nil
}
func (co *Compiler) compileArgSearch(sel *Select, arg *graph.Arg) error {
if sel.Ti.TSVCol.Name == "" {
return fmt.Errorf("no tsv column defined for %s", sel.Table)
}
if arg.Val.Type != graph.NodeVar {
return argErr("search", "variable")
}
ex := expPool.Get().(*Exp)
ex.Reset()
ex.Op = OpTsQuery
ex.Type = ValVar
ex.Val = arg.Val.Val
sel.addArg(arg)
setFilter(sel, ex)
return nil
}
func (co *Compiler) compileArgWhere(ti sdata.DBTableInfo, sel *Select, arg *graph.Arg, role string) error {
st := util.NewStackInf()
var err error
ex, nu, err := co.compileArgObj(ti, st, arg)
if err != nil {
return err
}
if nu && role == "anon" {
sel.SkipRender = SkipTypeUserNeeded
}
setFilter(sel, ex)
return nil
}
func (co *Compiler) compileArgOrderBy(sel *Select, arg *graph.Arg) error {
if arg.Val.Type != graph.NodeObj {
return fmt.Errorf("expecting an object")
}
var cm map[string]struct{}
if len(sel.OrderBy) != 0 {
cm = make(map[string]struct{})
for _, ob := range sel.OrderBy {
cm[ob.Col.Name] = struct{}{}
}
}
st := util.NewStackInf()
for i := range arg.Val.Children {
st.Push(arg.Val.Children[i])
}
obList := make([]OrderBy, 0, 2)
for {
if st.Len() == 0 {
break
}
intf := st.Pop()
node, ok := intf.(*graph.Node)
if !ok || node == nil {
return fmt.Errorf("17: unexpected value %v (%t)", intf, intf)
}
if node.Type != graph.NodeStr && node.Type != graph.NodeVar {
return fmt.Errorf("expecting a string or variable")
}
ob := OrderBy{}
switch node.Val {
case "asc":
ob.Order = OrderAsc
case "desc":
ob.Order = OrderDesc
case "asc_nulls_first":
ob.Order = OrderAscNullsFirst
case "desc_nulls_first":
ob.Order = OrderDescNullsFirst
case "asc_nulls_last":
ob.Order = OrderAscNullsLast
case "desc_nulls_last":
ob.Order = OrderDescNullsLast
default:
return fmt.Errorf("valid values include asc, desc, asc_nulls_first and desc_nulls_first")
}
if err := setOrderByColName(sel.Ti, &ob, node); err != nil {
return err
}
if _, ok := cm[ob.Col.Name]; ok {
return fmt.Errorf("duplicate column in order by: %s", ob.Col.Name)
}
obList = append(obList, ob)
}
for i := len(obList) - 1; i >= 0; i-- {
sel.OrderBy = append(sel.OrderBy, obList[i])
}
return nil
}
func (co *Compiler) compileArgDistinctOn(sel *Select, arg *graph.Arg) error {
node := arg.Val
if node.Type != graph.NodeList && node.Type != graph.NodeStr {
return fmt.Errorf("expecting a list of strings or just a string")
}
if node.Type == graph.NodeStr {
if col, err := sel.Ti.GetColumn(node.Val); err == nil {
sel.DistinctOn = append(sel.DistinctOn, col)
} else {
return err
}
}
for _, node := range node.Children {
if col, err := sel.Ti.GetColumn(node.Val); err == nil {
sel.DistinctOn = append(sel.DistinctOn, col)
} else {
return err
}
}
return nil
}
func (co *Compiler) compileArgLimit(sel *Select, arg *graph.Arg) error {
node := arg.Val
if node.Type != graph.NodeNum && node.Type != graph.NodeVar {
return argErr("limit", "number or variable")
}
switch node.Type {
case graph.NodeNum:
if n, err := strconv.Atoi(node.Val); err != nil {
return err
} else {
sel.Paging.Limit = int32(n)
}
case graph.NodeVar:
sel.Paging.LimitVar = node.Val
}
return nil
}
func (co *Compiler) compileArgOffset(sel *Select, arg *graph.Arg) error {
node := arg.Val
if node.Type != graph.NodeNum && node.Type != graph.NodeVar {
return argErr("offset", "number or variable")
}
switch node.Type {
case graph.NodeNum:
if n, err := strconv.Atoi(node.Val); err != nil {
return err
} else {
sel.Paging.Offset = int32(n)
}
case graph.NodeVar:
sel.Paging.OffsetVar = node.Val